Tandberg 3001A

Programmable FM Tuner (1980-94)

The Tandberg 3001 A is an analog tuner. By this I mean that it does not employ frequency-synthesized tuning. The analog approach was selected by Tandberg's talented engineers not so much because they could use a familiar (and perhaps easier-to-read) dial scale and dial pointer, but rather so that they could achieve the highest possible signal-to-noise ratios-in excess of 90 dB in mono and well over 80 dB in stereo.

The front-end employs eight ganged, tuned circuits to obtain startlingly high selectivity when needed. The tuning elements are voltage-controlled capacitance diodes, and dual-gate MOS-FETs are used in the r.f. and mixer stages. In addition to the main tuning system, there is a tuning circuit that permits eight preset FM station frequencies to be stored in memory. This particular circuit is based on a voltage-synthesis principle combined with a fast analog servo loop that achieves maximum signal-to-noise ratio and frequency stability.

The i.f. filter circuits can be switched to three different bandwidths (wide, normal, and narrow). These filters consist of phase-linear block filters, plus pure LC filters, to achieve high selectivity with extremely low distortion. The special limiter circuit used in this design provides exceptionally good AM and spurious-response rejection. In addition, it ensures a constant signal output over a very wide range of input signal levels.

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Type: Mono/Stereo Tuner
Tuning Bands: FM
Tuning Scale: Analogue
FM Tuning Range: 87.5 to 108 MHz
Sensitivity: 5.0uV (FM)
Signal to Noise Ratio: 92dB (FM)
Distortion: 0.1% (FM)
Selectivity: 30dB (FM)
Frequency response: 30Hz to 15kHz (FM)
Dimensions: 435 x 350 x 83mm
Weight: 7kg